IntroductionPulmonary hypertension (PH) may occur in patients with antisynthetase syndrome (ASS) but this association is poorly studied. In this article, we report 4 new cases of PH associated with ASS, and we discuss PH mechanisms in this specific disease. CasesFour patients (3 females, 1 male) with confirmed ASS associated with anti-Jo1 (n=3), anti-PL7 (n=1), and anti-Ro52 (n=3) antibodies were analyzed. They presented with subacute dyspnea in average ten years after they were first diagnosed as ASS. Diagnosis of pre-capillary PH was made (mean of mPAP: 34mmHg): PAH (n=1), group 3 PH (n=2) and PH associated to hyperthyroidism (n=1). Among three patients who received specific PAH therapy, two had significant improvement in both clinical and hemodynamic parameters. ConclusionDuring ASS, PH may occur in 5 to 10 % of cases, caused by various mechanisms. Unexplained dyspnea may be due to PH among ASS patients.